In one well-known arrangement for operating a textile winding station of a textile winding machine, a sensing device is provided for sensing the presence and quality of a yarn being wound from a supply package onto a take-up package such as, for example, a cross wound package. In the event that the sensing device senses an out-of-limits condition such as, for example, a portion of the yarn which does not meet the quality requirements, the defective portion of the yarn is severed and removed while the two yarn ends created by the severing process are spliced together and the yarn winding operation is then resumed. In addition to deliberately initiating severing of the yarn such as just described, the yarn itself may break due to a weak defective portion of the yarn and, in such circumstances, the sensing device senses that the yarn is no longer traveling through the sensing area and alerts a control unit which shuts down the yarn winding operation. Typically, a winding re-establishment procedure is then implemented by which a yarn end from the take-up package and a yarn end from the supply package are spliced together so that the yarn winding operation can be restarted.
One such out-of-limits operational condition is a condition in which the yarn has moved out of its normal travel path which extends within the sensing range of the sensing device, although the yarn still extends between the supply package and the take-up package. Such an out-of-limits operational condition may occur if debris or other matter accumulates on the yarn or on a component of the textile winding machine over which the yarn travels, which may lead to a situation in which the yarn moves away from the surfaces of the textile winding machine which normally guide the yarn during its travel without, however, causing a yarn break. However, once the yarn moves beyond the sensing range of the sensing device, the sensing device transmits a signal to the control unit of the textile winding machine which shuts down the yarn winding operation. Unfortunately, a textile winding station which does not possess the capability to distinguish between a true yarn break situation and another shutdown-causing situation in which the yarn has not broken will react to a signal from the sensing device as if a true yarn break has occurred and this approach does not guarantee that the actual out-of-limits operational condition will be remedied.
Other out-of-limits operational conditions which may lead to a shutdown of the yarn winding operation include the occurrence of electrical disturbances such as, for example, fluctuations of at least a certain magnitude in the electrical power system leading to fluctuations in the voltage supply to the sensor. Another out-of-limits operational condition is the accumulation of dirt or debris on or in the vicinity of the sensing device which causes the sensing device to falsely conclude that it has detected a defective portion of the yarn traveling therepast. Such a situation may occur, for example, during the passage through the sensing device of a so-called core yarn which does not have fibers wound around it but, instead, is merely a blank strand of material which, as a rule, is a monofilament. A sensing device which is covered or clouded by dust or debris may falsely conclude that no yarn is present when, in fact, the core yarn is traveling through the sensing device. As a result, the control unit will shut down the yarn winding operation at the textile winding station on the assumption that a yarn break has occurred when, in fact, no yarn break has occurred.
In U.S. Pat. No. 4,804,151, a yarn severing operation is disclosed in which a yarn severing device severs a yarn extending between a supply package and a take-up package during a shutdown of the textile winding station independent of the reason for the shutdown of the textile winding station. In this arrangement, each time the textile winding station is shut down, the yarn severing device is operated to sever the yarn and, subsequently, the two yarn ends created by the yarn severing process are then spliced together. The yarn severing process is implemented even if the shutdown of the textile winding station is not due to any defect in the yarn but, instead, is due to some other reason. However, if the reason for the shutdown of the textile winding station is due to an out-of-limits operational condition other than a defect in the yarn, merely severing the yarn and splicing the yarn ends together may not remedy the out-of-limits operational condition and, upon restarting of the yarn winding operation, another shutdown of the textile winding station will occur very shortly after the restarting. Accordingly, the need exists for an improved method and apparatus for re-establishing a yarn winding operation at a textile winding station after a yarn winding operation has been stopped due to the detection of an out-of-limits operational condition.